Isoceles Triangles

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Isoceles Triangles

by exhilaration » Sat May 30, 2009 11:44 am
Hi,

Is the fastest way to solve this problem by working backwards from each answer choice until you match their perimeter or is there a faster way to solve this?

Thanks.
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by Katrusya » Sat May 30, 2009 12:30 pm
a is a side of right triangle.
b is a hypotenuse.
b=a*sqr2

Perimeter = 2a+a*sqr2=16+16*sqr2
a = 8*sqr2
b = a*sqr2= 8*sqr2*sqr2=16

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by blackarrow » Sat May 30, 2009 1:17 pm
exactly the approach

Isoceles traingle 2 sides= x and x

Third side = x root 2

Thus perimeter = 2x+x root2 = 16+16 root 2. ...

How the equation is solved is by equating 2x=16root2. Thus x=8root2

Hypotenuse = 8root 2*8 root 2= 16
Its better to burn out than to fade away

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by exhilaration » Sat May 30, 2009 1:20 pm
blackarrow wrote:exactly the approach

Isoceles traingle 2 sides= x and x

Third side = x root 2

Thus perimeter = 2x+x root2 = 16+16 root 2. ...

How the equation is solved is by equating 2x=16root2. Thus x=8root2

Hypotenuse = 8root 2*8 root 2= 16
wicked. thanks.